The amount of energy you can store in this type of interaction is not very significant compared to other forms of solar storage. Batteries are one class of stor

The amount of energy you can store in this type of interaction is not very significant compared to other forms of solar storage. Batteries are one class of storage methods, but what's even better is to use solar energy to split water molecules and store it in molecular hydrogen and oxygen (H2 and O2). These can be recombined in a fuel cell to produce water (with no loss in molecules) and produce electricity. A much, much greater energy density, far greater than any existing battery would be in such devices. Water-Splitting using natural sunlight is a difficult problem and many research groups at top institutions are working on it. The best known group in this field is Prof. Daniel Nocera at MIT. His research is being commercialized by the company Sun Catalytix and there are plenty of YouTube videos of him speaking and explaining his research. There are other research groups as well. The vision for the future is a distributed electrical grid. Each home or building would have a reactor on top that would contain a water-splitting catalyst producing hydrogen and oxygen gas, which can be stored indefinitely under pressure and then released into a fuel-cell device that would recombine to form water (that can be placed into the reactor) and electricity (for consumption). This would be an efficient way to capture much more of the sun's energy than current photovoltaics and is an entirely closed cycle.